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Dimensionally Dependent Tensor Identities by Double Antisymmetrisation

S. Brian Edgar·A. Hoglund
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Abstract

Some years ago, Lovelock showed that a number of apparently unrelated familiar tensor identities had a common structure, and could all be considered consequences in n-dimensional space of a pair of fundamental identities involving trace-free (p,p)-forms where 2p >= n$. We generalise Lovelock's results, and by using the fact that associated with any tensor in n-dimensional space there is associated a fundamental tensor identity obtained by antisymmetrising over n+1 indices, we establish a very general 'master' identity for all trace-free (k,l)-forms. We then show how various other special identities are direct and simple consequences of this master identity; in particular we give direct application to Maxwell, Lanczos, Ricci, Bel and Bel-Robinson tensors, and also demonstrate how relationships between scalar invariants of the Riemann tensor can be investigated in a systematic manner.

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S. Brian Edgar, A. Hoglund. 2001-05-18. Dimensionally Dependent Tensor Identities by Double Antisymmetrisation. https://doi.org/10.1063/1.1425428

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